Quick answer
What is insulin used for?
Insulin is a hormone medicine that lowers blood glucose levels. It is essential for everyone with type 1 diabetes and is sometimes needed in type 2 diabetes once tablets are no longer enough. Insulin types vary by speed and duration, often combined in a basal-bolus regimen, and your diabetes team teaches injection technique and hypoglycaemia treatment.
Why insulin is needed
In type 1 diabetes, the body no longer produces its own insulin, so replacing it with injected insulin is essential for survival. In type 2 diabetes, insulin is used to supplement beta cells in the pancreas that are gradually failing to produce enough insulin on their own, usually once other tablets are no longer keeping blood glucose in range.
How insulin regimens work
Most regimens combine a background dose with doses around meals. Basal insulin is taken once or twice daily to provide a steady background level, while bolus insulin is taken with meals and adjusted according to the amount of carbohydrate eaten, particularly in type 1 diabetes.
Injection technique for insulin
Insulin is usually injected using short needles into the abdomen or thighs. Rotating the injection site between doses helps prevent lipohypertrophy, a lumpy thickening of the skin and fat that can develop with repeated injections in the same spot.
Recognising and treating hypoglycaemia
Hypoglycaemia, or a hypo, can cause shaking, sweating and confusion, and should be treated promptly with fast-acting glucose. In a severe hypo where someone becomes unconscious, glucagon may be needed as an emergency treatment.
Common questions about insulin
- What types of insulin are there?
- Insulin comes in rapid-acting types such as Novorapid, long-acting types such as Lantus or Levemir, and pre-mixed combinations. Your diabetes team chooses and individualises the regimen that suits your lifestyle and blood glucose patterns.
- How do I treat a hypo (low blood sugar)?
- Take a small amount of fast-acting glucose, such as jelly babies or glucose tablets, then recheck your blood glucose after 15 minutes. Repeat if it is still low, and follow up with a longer-acting carbohydrate once you feel better.
- Does insulin cause weight gain?
- Weight gain is a common effect of starting insulin, and your diabetes team can offer dietary advice to help manage it. For many people it is a necessary trade-off for achieving better blood glucose control.
- What should I do if I miss an insulin injection?
- Never double up on a missed dose to make up for it. Follow the specific instructions your diabetes team has given you, and contact them if you are unsure what to do.